If you haven't heard about this book, check this out.
There is a lineage of books here, a tree.
It all starts with Zen and Art or Archery, goes to 'The Inner Game of Tennis' (great great book to read)
Goes to, 'Zen and Art or Motorcycle Maintenance'
'Effortless Mastery' I think comes from this tree of books. They are all great and Kenny's book is great.